Ester interchange



ESTER INTERCHANGE I No Drawing. Filed Jan. 27, 1960, Ser. No. 4,888

' 6 Claims. (Cl. 260-461) -"This invention relates to the preparation of esters of phosphorous acid.

It is an object of the present invention to develop an improved process for preparing tertiary phosphites of high boiling alcohols. V

Another object is to prepare such phosphites having improved physical properties and particularly having improved purity.

. A- further object is to prepare novel phosphites.

I Still further objects and the entire scope of applicamay of the present invention will become apparent fro'rnthe detailed description given hereinafter; it should be Understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention,.are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description,

It has now been found that these objects can be attained by transesterification of tris 2-chlorpropyl phosphite with a higher boiling monohydric orpoiyhydric alcohol.

Preferably, tris 2-chlorpropyl phosphite is employed.

In place of tris 2-chlorpropyl phosphite, less preferably there can be employed tris 2-chlorbutyl phosphite, As the' higher boiling mouohydric alcohol there are employed alcohols having higher boiling points than propylene chlorhydrin. Among such alcohols are alkanols and cycloalkanols, such as n-hexanol, n-hentanol, n-octanol, Z-ethyl hexanol, isooctyl alcohol, octanol-2, 2- methyl heptanol-2, u-decyl alcohol, isodecyl alconol, liauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohoL-cyclehexanol, methyl cyclohexanol, alkanediols orgiycols such as ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 1,6-hexanediol, piuacol, 1,2- pentanediol, 2-methyl-2,4-pentanediol, 1,3-butyleue glycol, neopentyl glycol}2-ethyl-1,3-hexanediol, 2,4-pentanediol, 2,4-heptanediol, 2,2-diethyl-1,3-propanediol, 2- ethyl-Zn-butyl-1,3-propanediol, and also pentaer'ythritol. -"-The present invention is particularly valuable in preparing the tris alkyl phosphites from alkanols having 6 to 12 carbons.

The transesterification between the tris 2-chlorpropyl phosphite and the alcohol can be carried out at any temperature from room temperature to the boiling point of propylene chlorhydrin, at the pressure employed. Thus,.at atmospheric pressure the reaction can be carried out at temperatures up to 133 C. The reaction can be carried out at atmospheric, or subatmospheric pres: sure. Preferably, the pressure is subatmospheric, e.g., 50 mm. or less. The propylene chlorhydrin formed is I Patented Nov. 2 2 1960 transesterification has. a boiling point which is 50 C.

Lower than the boiling point of phenol. Hence, the products can be isolated at a lower temperature than when using triphenyl phosphite as the transesterifying agent. Additionally, when using triphenyl phosphite, an alkaline catalyst is employed.

The products obtained according to the present invention, e.g., the tris higher alkyl phosphites, are water white and are of an excellent purity. In this respect they are superior to the same phosphites prepared using present commercial procedures or tri 2-chlorethyl phosphite as the transesterifying agent; 7

, On a commercial basis the overall reaction is as follows:

' can be continuously regenerated.

R in the" formulae stands for the alkyl group. It is thus evident that the propylene oxide starting material tion, the by-product propylene chlorhydrin formed in phite, distearyl 2-.chlorpropyl phosphite, dimethyl 2 distilled oil and the desired phosphite is recovered as 2' the residue from such distillation. t It is also possible to carry out the reaction at atmos-. pheric pressure and then separate the desired phosphite ester-from the propylene chlorhydrin formed by distillation at reduced pressure, e.g.,.25.mm..or.1ess::"

tris .2-chlorpropylphosphite -(e.g., 3 moles? oiflel ylene V, g

the transesterification is less toxic than the by-product ethylene chlorhydrin. Furthermore, it has been found that the products made from tris chlorpropyl phosphite interesterification are easier to control and work up and have reduced acid numbers (the acid number indicates the residual acid in the product). For example, tri n-decyl phosphite prepared from tris V2-chlorethyl phosphite and n-decyl alcohol had an acid number of 5-10, whereas when tris 2-chlorpropyl phosphite was used as the transesterifying agent, the acid number was 0.02-0.51

In order to insure complete ester interchange using a monohydric alcohol there should be employed at least 3 moles of the alcohol per mole of the tris 2-chlorpropyl phosphite. Generally, from 1-15 molar excess of the alcohol is employed to insure formation of the trialkyl ester. No advantage has been found in using over 15% excess alcohol and, in general, 10-15% excess of the alcohol gives the best commercial quality product. The use of larger amounts of the alcohol means that more alcohol must be recovered in the subsequent distillation. If less than three moles of the monohydric alcoholare employed then mixed phosphites are obtained. Thus when 2 moles of the monohydric alcohol are employed per mole of tris 2-chlorpropyl phosphite there are ob-. tained compounds such as, diceryl Z-chlorpropyl' phoschlorpropyl phosphite Where one mol of monohydric phitethere are obtained compounds such as hexyl. di-2- chlorpropyl phosphite, stearyl di-Z-chlorpropyl phosphite, methyl. di-2-chlorpropyl phosphite, and decyl di-2 -chl 'or-, propyl phosphite.- p e When using 11,}? or my glycols, 'ifjone equivalentior; more) -ofpblyhydric alcohol is usedyper equivalenta'of glycol with 2 moles of 2 chlorpropyl phosphite) there are formed products of the following type:

where R R R R R and R are hydrogen or lower alkyl and n is or 1. Examples of such compounds are bis (4,4,6-trimethyl 1,3,2- dioxaphosphorinanoxy) 1,1,3 propane, bis(1,3',2-dioxaphospholanoxy) ethane? bis(4- methyl 1,3,2 dioxaphospholanoxy) 1 -;merh 1etnane; bis(4,5 dimethyl 1,3,2 dioxaph'ospholanoxy) 1 ethylethane; bis(4,4,5,5 tetramethyl 1,3,2 dioxaphospholanoxy) 1,l,2,2 tetramethylethane; bis(4 propyll,3,2 dioxaphospholanoxy) 1 proxyleth'ane; bis(l,3 ,2- dioxaphosphorinanoxy) propane; bis(4 methyl 1,3,2 dioxaphosphorinanoxy) 1 methylpropane; bis(5,5-dimethyl 1,3,2 dioxaphosphorinanoxy)-2,2:dimethylpropane; bis(4 propyl ethyl 1,3,2 diox'aphosphorinauoxy) l propyl 2 ethylpropane; bis(4 propyl 6 methyl 1,3,2 dioxaphosphorinanoxy) 1 propyl 3 methylpropane; bis(5,5-diethyl 1,3,2 dioxaphosphorinanoxy)-2,2-diethyl propane; bis(5 ethyl 5 butyl- 1,3,2 dioxaphosphorinanoxy) 2 ethyl 2 butylpropane; and bis(4-propyl 1,3,2 dioxaphosphorinanoxy)- l-propylpropane.

If less than one equivalent of diol is employed then monomeric products are formed which still have a chlorpropyl group. Thus, when reacting one mol of tris 2- chlorpropyl phosphite with one mol (or less) of a diol having 2 to 3 carbon atoms separating the hydroxyl groups, there are formed products of the formula:

where R R R R R and R are hydrogen or lower alkyl and n is either 0 or 1. Examples of compounds coming within this formula are 2-(2-chloro)propyl l-4,4,6- trimethyl-1,3,2 dioxaphosphorinane; 2 (2 chloro) propoxy 1,3,2 dioxaphospholane; 2 (2 chloro)pro' poxy 4 methyl 1,3,2 dioxaphospholane; 2 (2 chloro)propoxy 4,5 dimethyl 1,3,2 dioxaph'ospholane; 2-(2 chloro)propoxy 4 ethyl 1,3,2 dioxaphospholane; 2-(2 chloro)propoxy' 4,4,5,5'- tetramethyl 1,3,2 dioxaphospholane; 2 (2 chloro).propoxy 4 propyl 1,3,2 dioxaphospholane; 2-(2-chloro) propoxy 1,3,2 dioxaphosphorinane; 2 (2 chloro) propoxy 4 methyl 1,3,2 dioxaphosphorinane; 2-(2- chloro)-propoxy 5,5 dimethyl 1,3,2 dioxaphosphorinane; 2 (2 chloro)propoxy 4-propyl 5 ethyl- 1,3,2-dioxaphosphorinane; 2 (2 chloro)propoxy 4 propyl-6-methyl 1,3,2 dioxaphosphorinane; 2 (2 chlor)propoxy 5,5 diethyl 1,3,2 dioxaphosphorinane; 2 (2-chloro)propoxy 5 -etl1yl 5-butyl-l,3,2- dioxaphosphorinane; 2-(2-chloro)propoxy 5 ethyl 5- butyl 1,3,2 dioxaphosphorinane; 2-(2-chloro)propoxy- 4-propyl-1,3,2-dioxaphosphorinane.

The compounds containing a 2-chlorpropoxy group and a 5 or 6 member heterocyclic ring are new compounds as are the compounds having two heterocyclic rings joined through an oxyalkyleneoxy bridge. They are useful as stabilizers and plasticizers for vinyl chloride resins and other plastics. They are also useful as insecticides. The other tertiary phosphites disclosed likewise are useful as plasticizers and stabilizers for vinyl chloride resins.

When 2 mols oftn's 2-chlorpropyl phosphite are re-' acted with 1 mol of entaeryuiritol there is formed a 311 grams (1 mol) of tris 2-chlorpropyl phosphite were mixed with 534 grams (3 moles +12.7% excess) of isodecyl alcohol. The mixture was then distilled in a vacuum at 10-15 mm. until the pot temperature was C. The triisodecyl phosphite recovered from the pot was water white, had an acid number well below 0.5 an N of 1.4540 and a d of 0.898.

Example 2 Example 1 was repeated utilizing 534 grams of ndecyl alcohol in place of the isodecyl alcohol. There was obtained tri n-decyl phosphite in excellent yields.

Example 3 Moles Tris 2-ch1orpropyl phosphit'e 1 n-oetanol 3 The process of Example 1 was repeated and there was recovered tri n-octyl phosphite of excellent purity.

Example4 Moles Tris 2-chlorpropyl phosphite 1 2-ethylhexanol 3.4

The process of Example 1 was repeated and the tri 2- ethylhexyl phosphite recovered as a water white liquid had the following properties: N 1.4489; d 0.915.

Example 5 Moles Tris 2-chlorpropyl phosphite 1 Isooctyl alcoho 3.3

The process of Example 1 was repeated and triisooctyl phosphite wasrecovered.

Example 6 Moles Tris 2-chlorpropyl phosphite a ....-a..-..-- 1 n-Hexyl alcohol v 3.3

The process of Example 1 was repeated and tri n-hexyl phosphite was recovered.

Example 7 Moles Tris 2'-chlorpropyl phosphitenn l Cyclohexanol 3.2

The process of Example 1 was repeated and tricyclohexyl phosphite was recovered.

Example 8 Moles Tris 2-chlorpropylphosphite -2- 1 Lauryl alcohol 3.3

The process of Example 1 was repeated and trilauryl phos'phite was recovered.

Example 9 Mold! Tris 2-chloropropyl phosphite I Stearyl alcohol- 3.3

The process of Example 1 was repeated and tristearyl phosphite was recovered.

Example '10 Moles Tris 2-chloropropyl phosphite 2 Ethylene glycol 3 The process of Example 1 was repeated and his (1,3,2 dioxaphospholanoxy) ethane having the formula CHz-O OCH2 was recovered.

Example 11 Moles Tris Z-chlorpropyl phosphite 1 Decyl alcoh l 2 The proce5s of Example 1 was repeated and there was recovered di decyl 2-chlorpropyl phosphite.

Example 12 Moles Tris 2-chlorpropyl phosphite 2 Pinacol 3 The process of Example was repeated and there was recovered bis '(4,4,5,S-tetramethyl, 1,3,2-di'oxaphospholanoxy)-1,1,2,2-tetramethylethane.

Example 13 Moles Tris 2-chlorpropyl phosphite 2 2-methyl-2,4-pentanediol 3 The process of Example 10 was repeated and there was recovered bis (4,4,6-trimethyl-1,3,2-dioxaphosphorinanoxy) 1,1,3-trimethylpropane.

Example 14 Moles Tris Z-chlorpropyl phosphite 1 Decyl alcohol 1 The process of Example 1 was repeated and there was recovered decyl di-Z-chlorpropyl phosphite.

Example 15 Moles Tris chlorpropyl phosphite l Stearyl alcohol 1 The process of Example 1 was repeated and there was recovered stearyl di-Z-chlorpropyl phosphite.

Example 16 Moles Tris 2-chlorpropyl phosphite 1 Stearyl alcohol 2 The process of Example 1 was repeated and there was recovered di stearyl 2-chlorpropyl phosphite.

Example 17 Moles Tris 2-chlorbutyl phosphite l Z-ethylhexanol 3.3

The process of Example 1 was repeated and there was recovered tri 2-ethy1hexy1 phosphite as the still residue.

Example 18 Moles Tris 2-chlorbutyl phosphite 1 n-Decyl alcohol 3.2

The process of Example 1 was repeated and there was recovered tri decyl phosphite as the still residue.

Example 19 Moles Tris 2-chlorpropyl phosphite 2 Pentaerythritol 1 The process of Example 1 was repeated and there was recovered bis (Z-chlorpropoxy) spiro 1,3',2phosphorinaiie having the formula: i i i cmo r tomor o' POCH281HCH:

OCH: orno t as ajvery viscous, slightly yellow liquid 5 ,1. 5012 f, d 1.355.

ExampleZO Moles Compound of Example 19 1 Decyl alcohol 2 OCH: CH2.O/ V z where R is an alkyl group are obtained. These materials can be used as plasticizers for vinyl chloride resins.

Example 21 Moles Tris 2-chlorpropyl phosphite 1 1,2-propanediol 1 The process of Example 1 was repeated and there was discovered 2-(2-chloro) propyl-4-methyl-1,3,2-dioxaphospholane.

Example 22 Moles Tris 2-chlorpropyl phosphite 1 1,3-propanediol l The process of Example 1 was repeated and there was recovered 2-(2-chloro) propyl-1,3,2-dioxaphosphorinane.

Example 23 Moles Tris Z-chlorpropyl phosphite 1 2,3 butanedinl 1 The process of Example 1 was repeated and there was recovered 2-(2-chloro) propyl-4,5-dimethyl-1,3,2-dioxaphospholane.

Example 24 Moles Tris 2-chlorpropyl phosphite l Ethylene glycol 1 The process of Example 1 was repeated and there was recovered 2-(2-chloro) propyl-l,3,2 dioxaphospholane.

Example 25 Moles Tris 2'chlorpropyl phosphite 1 Neopentyl glycol- 1 The process of Example 1 was repeated and there was recovered 2-(2-chloro) propyl-5,5-dimethyl-1,3,2-di'oxaphospholane.

Example 26 Moles Tris 2-chlorpropyl phosphite 1 Butanediol-l ,3 1

The process of Example 1 was repeated and there was recovered 2-(2-chloro) propyl-4-methyl-1,3,2-dioxaphosphorinane.

Example 27 Moles Tris 2-chlorpropyl phosphite 1 2,2-dimethyl propanediol-1,3 1

Moles Tris 2-chlorpropy1 phosphite 1 2-ethyl-2-n-butyl-1,3-propanediol 1 The process of Example 1 was repeated and there was recovered 2-(2-ch1oro) propyl fi-ethyl-s-hutyl-1,3,2-dioxaphosphorinane.

What is claimed is:

1. Cyclic phosphites having the formula (RP R)h P-OCHzCHClCH:

where R R R R R and R are selected from the group consisting of hydrogen and lower alkyl groups,

8 and n is an integer of the group consisting of 0 and l.

2. Cyclic phosphites having the formula wherein R and R are selected from the group consisting of alkyl having 6 to 18 carbon atoms in the alkyl group and 2 chlorpropyl.

3. A compound according to claim 2 wherein both R and R are decyl.

4. A compound according to claim 2 wherein both R; and R are stearyl.

5. A compound according to claim 2 wherein R and R are both lauryl.

6. Bis (4,4,6-trimethy1-1,3,2-dioxaphosphorinanoxy) 1, 1,3-trimethyl propane.

References Cited in the file of this patent UNITED STATES PATENTS 2,834,798 Hechenbleikner et a1. May 13, 1958 2,841,608 Hechenbleikner et a1. July 1, 1958 2,883,411 Lanham Apr. 21, 1959 Netiee of Adverse Deeisien in Iiiterfereiiee In Interference No. 93,252 involving Patent No. 2,961,454, H. Gould and J. P. fiakus, Ester interchange, final deeislon adverse to the pa tentees was rendered Aug. 21, 1963, as to claim 3.

[Ofiioial Gazette Nowembm' 12, 1963.] 

2. CYCLIC PHOSPHITES HAVING THE FORMULA 